edited by Regina Cowen Karp
Oxford University Press, 1993
Buku Teks
Westview Press, 1989
Buku Teks
Westview Press, 1989
Buku Teks
East, Roger
Pinter Publishers, 1997
Buku Teks SO
edited by Andrew Blasko, Diana Januauskiene
Council for Research in Values and Philosophy, 2008
Buku Teks SO